Saturn: Moons: Methone
Methone (pronounced me-thoh-nee; adjective: Methonean) is a tiny 3-kilometer (2-mile) diameter moon that orbits between Mimas and Enceladus at a radius of 194,000 kilometers (120,546 miles) from Saturn. Scientists have two theories to explain the presence of Methone and two other tiny sister moons, Pallene and Anthe. First, the three moons may have split from either Mimas or Enceladus. Second, all five moons may be the remains of a larger swarm that traveled in that area close to Saturn. Methone orbits Saturn in 24 hours.
Because these three tiny moons (Methone, Pallene and Anthe) orbit at very similar distances from Saturn, they are in a dynamical relationship. Mimas strongly perturbs the three moons, all of which orbit between Mimas and the Enceladus. The vastly more massive Mimas causes the Methone orbit to vary by as much as 20 kilometers (12.4 miles), causes Pallene to vary by a slightly smaller amount, and has the greatest effect on Anthe.
These three moons may also be contributing particles to Saturn's E-ring. The moons are small and were only recently discovered. Consequently, astronomers have few details on characteristics of these moons such as reflectivity (albedo), rotation (probably tidally locked on Saturn because they are so close), and composition.
Discovery
The Cassini Imaging Team discovered Methone on June 1, 2004. Methone and nearby Pallene were the first moons discovered in Cassini images.
Origin of Names
John Herschel suggested that the moons of Saturn be associated with Greek mythical brothers and sisters of Kronus, known to the Romans as Saturn. The name Methone comes from the name in Greek mythology of one of seven Alkyonides, daughters of the god (or Titan) Alkyoneus who was born of Gaia and the blood of Uranus. Herakles (Hercules) killed their father in the war between the gods of Mount Olympus and the titans. Overcome by grief, the seven daughters threw themselves into the sea to die, but the goddess Amphitrite took pity on them and transformed them into halcyons or kingfishers.
Astronomers also refer to Methone as Saturn XXXII or S/2004 S1. The International Astronomical Union now controls the official naming of astronomical bodies.